1. Field of the Invention
The present invention relates to a solid electrolytic capacitor and a method for manufacturing same, and particularly to a solid electrolytic capacitor in which an anode section of a capacitor element is electrically connected to an anode terminal through a pad member and a method for manufacturing same.
2. Description of Related Art
FIG. 9 is a cross sectional view of a conventional solid electrolytic capacitor. As shown in FIG. 9, the conventional solid electrolytic capacitor comprises a solid electrolyte type capacitor element 100, an anode terminal 111, and a cathode terminal 112, which are buried in an enclosure resin 120. The capacitor element 100 has a dielectric layer 103 formed on a surface of an anode body 101 in which an anode lead 102 is planted, an electrolyte layer 104 formed on the dielectric layer 103, and a cathode layer 105 formed on the electrolyte layer 104.
The anode terminal 111 and the cathode terminal 112 include an anode terminal surface 115 and a cathode terminal surface 116, respectively, which are exposed on a lower surface 120a of the enclosure resin 120. To a surface of the anode terminal 111 on the opposite side to the anode terminal surface 115, joined electrically is a pad member 114 by welding means such as laser welding or resistance welding. A tip end part 102a of the anode lead 102 of the capacitor element 100 is electrically connected to an end part of the pad member 114. To a surface of the cathode terminal 112 on the opposite side to the cathode terminal surface 116, electrically connected is a part of a surface of the cathode layer 105 of the capacitor element 100.
However, in a case where the pad member 114 is joined to the anode terminal 111 by laser welding, conventionally, as shown in FIG. 10, the laser welding is performed on facing surfaces of the pad member 114 and the anode terminal 111 at a position adjacent to a lateral surface 114a of the pad member 114 located on the opposite side to the cathode terminal 112, thereby forming a joint part 130 of the pad member 114 and the anode terminal 111.
Also, in a case where the pad member 114 is joined to the anode terminal 111 by resistance welding, it was not possible to specify a position of the joint part 130 formed on the facing surfaces of the pad member 114 and the anode terminal 111.
Therefore, in a case of performing a cutting process on the pad member 114 in order to decrease the size of the pad member 114 to increase a space factor of the capacitor element 100, the joint part 130 of the pad member 114 and the anode terminal 111 might be cut off, and therefore, a poor electric connection might occur between the pad member 114 and the anode terminal 111.
Therefore, in a conventional solid electrolytic capacitor, in order to maintain a good electric connection between the pad member 114 and the anode terminal 111, the pad member 114 is buried in the enclosure resin 120 without performing a cutting process on the pad member 114 which is joined to the anode terminal 111 as shown in FIG. 9. Because of this, there has been a problem of decrease in the space factor of the capacitor element 100 in the conventional solid electrolytic capacitor.